A clothes treatment apparatus refers to an apparatus that washes laundry using friction between a drum and laundry and friction between laundry and wash water by rotating the drum placed in a tub, or an apparatus that dries laundry stored in a drum.
A conventional clothes treatment apparatus includes a cabinet forming an external appearance, a tub installed in the cabinet, a drum rotatably installed in the tub to wash laundry received therein and a power generating device to rotate the drum.
Meanwhile, the power generating device generally rotates the drum using a direct drive method or a belt pulley method.
The direct drive method employs a stator fixed to a rear surface of the tub, a rotating shaft penetrating the tub and connected to the drum and a rotor to which the rotating shaft is fixed, the rotor being rotated by a magnetic field generated by the stator. The belt pulley method is a method to rotate a pulley, coupled to a rotating shaft that penetrates the tub and is connected to the drum, using the power generating device via a belt.
In the case of the clothes treatment apparatus in which the drum is rotated using the belt pulley method, change in a rotation direction of the drum or sudden braking of the drum is difficult and the belt causes noise generation.
In the case of the direct drive method, vibration of the power generating device is transmitted to the tub and generates noise.
In addition, the power generating device used in the direct drive method must have a great capacity to apply large torque to the drum. However, the great capacity of the power generating device increases power loss (efficiency deterioration) and the volume of the power generating device.
Meanwhile, some power generating devices usable with the clothes treatment apparatus may include a planetary gear, which contributes to reduction in volume of the power generating device and provides large torque to the drum.
However, the power generating device using the planetary gear suffers from low efficiency, generation of noise or vibration and a complicated configuration (an increased number of constituent elements) because power provided by a sun gear is transmitted to the rotating shaft of the drum through the planetary gear.